FR2942862A1 - CONNECTION DEVICE FOR TRANSFER OF FLUID, INCORPORATING CIRCUIT AND METHOD OF MOUNTING / DISASSEMBLING THE SAME. - Google Patents

Abstract

The present invention relates to a connection device for a fluid transfer line, a fuel injector return circuit incorporating it, and a method for mounting / dismounting the device in a female connector to be connected to the male end. This device comprises: - connection means for mounting around a male end (1) being connected to a female end (10) and comprising a connecting end to be housed in a groove (13) of the female end, and - a locking member (30) of the connection means to be mounted around the male end to reversibly bring said connecting end into a locking position in said groove. According to the invention, this connection means is formed in one piece with this member and comprises a radially inner bearing zone (36) to be mounted against the male end and terminating in said connecting end, which comprises tabs (21) elastically deformable in the radial direction extending the bearing zone, each tab being adapted to be locked in the locking position by bending against the groove and against a ramp (7) for guiding and assisting the locking of the male end.

Description

CONNECTION DEVICE FOR TRANSFER OF FLUID, INCORPORATING CIRCUIT, AND METHOD FOR MOUNTING / DISASSEMBLING THE SAME.

The present invention relates to a connection device for a fluid transfer line, a fuel injector return circuit incorporating it, and a method for mounting / dismounting this device around a male tubular endpiece and in a nozzle. tubular female to connect to this male end. The invention is generally applicable to all connections between such tips transferring a fluid particularly at low pressure and in particular to fuel injection ramps for motor vehicles. Generally speaking, it is known for fuel injection ramps to use male tubular nozzle connecting devices which are sealed in a female tubular nozzle or cannula, by means of a nozzle. flexible connecting member which is mounted integral with the male end and which is lockable at its axially inner end in an inner circumferential groove of the female end under the control of a locking member cooperating with an axially outer portion of this member link. One can for example cite the document WO-A-2007/042344 which has such a device where the connecting member comprises two diametrically opposed axial arms which are integrally formed with the male end and which come to lock elastically. in the groove of the female end by a bending applied thereto in the radial direction, opposing their pulling axially outwards. A major disadvantage of these known connection devices is that when the male end is locked in the socket while the connecting member is not positioned in the connecting groove of the socket it is no longer possible later to bring the connecting member in this groove.

Another disadvantage of these known devices is that they require both separate parts (ie a connecting member making the connection in the groove of the socket and a locking member of this connecting member), which imposes an operation assembly of these parts not always easy and also a relatively high cost of the device due in particular to the use of different materials for these parts.

An object of the present invention is to propose a connection device for a fluid transfer line, in particular at low pressure, which overcomes these disadvantages and which comprises: a connection means intended to be mounted around a nozzle male tubular being connected to a female tubular tip by a radially inner face thereof, said connecting means comprising an axially inner end connection adapted to be housed in a connecting groove of this inner face, and - an organ locking the connection means which is intended to be mounted around the male end to reversibly bring the connection end into a locking position in the groove. For this purpose, a device according to the invention is such that the connection means 20 is formed in one piece with the locking member of which it forms an axially inner end, this connecting means comprising a bearing zone radially internal end intended to be mounted against the male end and terminating in said connecting end, which comprises at least two elastically deformable tabs in the radial direction and extending the support zone radially outwards, the radially outer faces and internal of each lug being adapted to be locked in the locking position, by bending each lug respectively against said groove and against a corresponding ramp guide and locking aid that has the male end. In the present description, the expression "axially inner" or "axially inward" will mean a localization in the connected state along the axis of symmetry of the male and female ends which is directed towards the inside of the fitting, ie proximally to the connecting groove of the female end and, conversely, by the axially outer or axially outward expressions a location along this axis opposite (ie distally) of this groove. Note that these elastically deformable tabs in flexion forming the connecting end of the locking member according to the invention have the advantage of involving a reduced cost and easy assembly for the connecting device in comparison with the devices known to two parts, and also contribute to confer a mechanical resistance to tearing (ie the inadvertent rise in operation of this connecting end out of the groove of the socket) which is improved in comparison with that of the aforementioned known devices which contributes to the reliability of the connection even under high operating fluid pressure. In addition and contrary to the above-mentioned prior art, a connection device according to the invention makes it possible, even if the male endpiece is initially locked in the socket without correctly positioning the connection means in the connection groove. to make possible this subsequent positioning in this groove. It will also be noted that this connection end according to the invention with flexible tabs in the radial direction is able to be accurately guided in the groove by said ramps, just before locking it in the locked position in this groove, which is only possible in the groove. case of this positioning and which is also obtained by these ramps. Note further that the connection device according to the invention is able to exert a self-locking function in operation of the connection of the male end in the socket in the locking position, thanks to the radial compression force which is exerted by these ramps on the connecting tabs by plating them in the groove of the socket and which is all the stronger that the pressure of the fluid flowing in the male end is higher. This results in increased operational safety of this device even under high pressures. According to another characteristic of the invention, each connecting lug has its inner face which preferably has an oblique or slightly concave surface intended to be mounted in contact with an edge of said corresponding ramp in the locking position, and its face external having a convex surface whose radius of curvature is adapted to substantially match the profile of said groove in this position. Note that these connecting tabs advantageously have a reduced thickness to allow their radial deformation. Advantageously, the outer face of each lug may comprise two axially outer and inner oblique sections and a third intermediate section which are respectively intended to fit two flared edges and a flat bottom of said groove. According to another characteristic of the invention, said connecting lugs may each be in a circular arc and be interconnected by as many notches designed to make these lugs sufficiently deformable in radial bending.

According to another characteristic of the invention, the locking member may have essentially: a radially inner annular portion which is intended to be mounted in contact with the male end and which has an internal diameter greater than that of said zone of support that this portion overcomes, and - gripping means forming an axially outer end of the locking member, preferably two in number and diametrically opposed, these means each having a radial thrust surface which is intended to receive a thrust manual of an operator to the female end and which is supported and connected to this annular portion by a connecting portion extending axially and radially inwardly.

Note that this locking member is not in contact with the fluid, such as a fuel, its constituent material can be selected to have the optimum mechanical characteristics so that its axially inner connecting tabs deform elastically in bending. Advantageously, this connecting member is made of a plastic material such as a polyamide, without limitation. According to another preferred feature of the invention, at least one means for securing the connection of the connection means to said groove can be formed on the locking member in the immediate vicinity of its gripping means, and be designed to get stuck. directly under at least one radial projection of the male end in the locking position so as to oppose the output of the connecting lugs out of the groove by a rise of the locking member relative to the male end . The or each radial projection may be formed of a retaining tooth which extends radially outwardly a central bearing surface of the male end and in which is adapted to come jamming by clipping at least one tongue, which extends radially inwardly one of the gripping means and then form (s) means (s) for securing the connection by a high stop in the manner of a safety notch 2o. It will be noted that the connection device according to the invention then advantageously provides a securing of the connection of its connection end to the female end via the ramps blocking the tabs in the groove, on the one hand, and via the or each tongue cooperating in clipping with a corresponding radial projection of the male end, on the other hand. This preferred device of the invention with securing of the connection thus has a mechanical resistance to tearing very satisfactory, being able to withstand high pressure. Also advantageously, the locking member may further incorporate, preferably in combination with this means (s) for securing the connection, a visual locking indicator which is respectively visible and invisible on the male end in the unlocked and locked positions and which preferably comprises at least one axial pin which is formed in one piece with the locking member at its axially outer end being movable in translation inside a housing opening on a bearing surface of the male end. According to another aspect of the invention, the connecting device furthermore incorporates the male end on which the locking member is mounted, and this device is such that this male endpiece has said radially projecting ramps, spaced apart on its circumference and at the same axial height, each ramp preferably having: an upper oblique portion extending radially outwards and axially inwards at an acute angle to said ridge, and an axial portion extending axially inwards from this edge, each leg overlapping in the locking position these two oblique upper and axial portions on either side of this edge, so that these ramps alone block operating the corresponding tabs in said groove by deforming radially outwardly. According to an exemplary embodiment of the invention, the ramps each terminate in a lower oblique portion and are preferably two in number, being diametrically opposed on the male end, as are the tabs intended to come into contact with them. in the locking position. According to another characteristic of the invention, the male endpiece 25 may furthermore comprise, between these ramps, centering means which are capable of angularly guiding this male endpiece in translation in the female endpiece in order to facilitate the centering of the legs. connection to the inlet of said groove, and which preferably comprise axial ribs. According to another characteristic of the invention, the connecting device further comprises at least one preferably toric seal, which can be mounted or overmolded in a sealing groove of the male end adjacent to one end. axially inner of this male end and which is intended to be applied against the female end. A fuel injector return circuit according to the invention comprises a male tubular nozzle connected to a female tubular nozzle by a connection device according to the invention as defined above.

A method of assembly / disassembly according to the invention in the locking position of a connecting device as defined above around a male tubular end and in a female tubular endpiece to be connected to this male end, comprises the successive steps following for mounting the device: a) positioning the locking member around the male end, preferably such that said connecting tabs are located above said ramps, b) pushing the male end up to at the bottom of the socket to connect it to the latter, so that these tabs are located immediately above said connection groove, c) is exerted a thrust axially inwardly on the locking member to bring these tabs into the locking position, by their radial deformation in flexion in contact with said ramps, then d) for unlocking the device, it exerts a pull axially towards the outside on the locking member while maintaining the male end against the bottom of the female end. Advantageously, to implement step c), the aforementioned means (s) for securing the connection that the locking member has under said radial projection (s) are brought. the male end, preferably by clipping of at least one tongue forming this means under a corresponding retaining tooth forming the or each projection.

Other features, advantages and details of the present invention will emerge on reading the following description of an exemplary embodiment of the invention given for illustrative and non-limiting purposes, this description being made with reference to the accompanying drawings, of which: FIG. 1 is a partial axial sectional view of a female nozzle in which a connecting device according to the invention is intended to be mounted, FIG. 2 is an exploded perspective view of a connection device. According to the invention intended to be mounted in the female end of Figure 1, this device being mounted around a male end provided with a seal, Figure 3 is an assembled perspective view of the device of Figure 2 mounted on the same male end in an unlocked position of its connecting end to the female end, Figure 4 is an axial sectional view along the plane IV-IV of FIG. 3 of this device shown in this unlocked position inside the socket, FIG. 5 is an assembled perspective view of the device of FIG. 3 mounted on the same spigot, but in a position of FIG. 6 is an axial sectional view along the plane VI-VI of FIG. 5 of this device illustrated in this locking position inside the female end, FIG. an axial sectional view of this connection device locked in the socket similar to that of Figure 6 but also showing the self-locking effect obtained by this device in contact with the male end, and Figure 8 is a detail view of the connecting end of the device of FIG. 7 locked with this self-locking effect in the socket. The male tubular end 1 illustrated in particular in FIGS. 2 to 5 presents in a known manner, at its axially outer end (ie upper end), two branch connections 2 and 3 in the form of fir tails which extend symmetrically one end. the other relative to a support surface 4 for the operator that has this tip 1 and which is centered on the axis X of the latter (see Figure 4). The tip 1 also has a circumferential radial recess 5 (see FIGS. 2 and 4) for mounting the device 1. The female tubular tip 10 illustrated in FIG. 1, of the cannula type and of standard shape, essentially presents on its radially inner face 11, in the immediate vicinity of its axially upper end 12, a circumferential connecting groove 13 which is of substantially trapezoidal axial section and which is intended to receive an axially inner end connection end (ie lower in FIGS. The female end piece 10 also has, in the immediate vicinity of its axially inner end 14, a circumferential sealing zone 15 (visible in FIG. 4) intended to receive a sealing O-ring 16 (visible in FIGS. 2 and following) which is previously mounted or overmolded in a circumferential sealing groove 6 of the male end 1. From In known manner, the internal section of this socket 10 has a narrowing 17 axially below the groove 13.

According to the invention, the connecting end 20 of the device is formed by a plurality of radially deformable tabs 21 (two in number in this embodiment and in the form of lobes), which are included in a locking member 30. of the device by forming the lower end. As illustrated in Figures 2 to 4, this member 30 is made of a plastic material of good mechanical strength such as a polyamide, and it comprises in this embodiment: - two gripping means 31 and 32 diametrically opposed forming an upper end of the member 30 and having two radial surfaces 31a and 32a for receiving a manual thrust of an operator to the female end 10, two connecting portions 33 and 34 supporting and connecting these gripping means 31 and 32 to a annular portion 35 located below, 2942862 i0 each portion 33, 34 extending radially inwardly under a gripping means 31, 32, - this annular portion 35 cylindrical which is intended to be mounted in contact with the male end 1 from and above the recess 5 5 of the latter, - a bearing zone 36 which is radially innermost for the member 30 and which is intended to be mounted against the male end 1 directly below the recess 5, and - the two connecting tabs 21 in arcs which extend downward and radially outwardly the bearing zone 36 forming the lower end of the device, and which are each adapted to be locked in the locking position against the groove 13, by their bending generated by two corresponding ramps 7 for guiding these lugs 21 and locking aid, formed radially projecting on the male end 1.

More specifically, the tabs 21 are relatively thin and are interconnected by two notches 22 whose axial height is provided to make these lugs 21 elastically deformable in radial bending and can optionally provide a discontinuous geometry (also in arcs of circles) to the bearing zone 36. Each lug 21 has its internal face 23 which is oblique or slightly concave so as to be in contact with and on either side of an edge 7a of the corresponding ramp 7 in the locking position, and its outer face 24a to 24c which is convex with a radius of curvature matching the profile of the groove 13. As shown in Figure 8, this outer face comprises two oblique upper portions 24a and lower 24b 25 and a third intermediate section 24c respectively intended to marry the two flared edges 13a and 13b and the flat bottom 13c of the groove 13. As for the ramps 7, they are formed in a diametrically opposed manner on the male end 1 and at the same axial height as the tabs 21 they are intended to guide axially and to constrain radially, each ramp 7 having (see Figure 3) an oblique upper portion 7b extending radially outwardly and downwardly at an acute angle to the ridge 7a, a cylindrical axial portion 7c extending downwardly from this ridge 7a, and a lower oblique portion 7d. The male end 1 further comprises, arranged between the ramps 7, two centering rails 8 formed in this example of axial ribs, which are intended to angularly guide the tip 1 in translation in the female endpiece 10 to facilitate the centering of the tabs 21 at the entrance to the groove 13. According to another important aspect of the invention visible in FIGS. 3 to 7, the locking member 30 furthermore incorporates at its upper end a tongue 37 intended to provide a securing the connection of the lugs 21 to the groove 13 in cooperation with a retaining tooth 9 of the male end 1 (note that it would be possible alternatively to provide several tabs 37 cooperating with as many retaining teeth 9). The tongue 37 is formed on a radially inner edge of one of the two thrust surfaces 31a of the gripping means 31 and 32, and is designed to be wedged directly under the tooth 9 which extends radially outwardly the surface support 4 of the nozzle 1. Thus, by a reversible axial wedging, a safety notch for the locking position of the tabs 21 in the groove 13, since the clipping of the tongue 37 under the tooth 9 s' opposed to the inadvertent rise of the locking member 30 around the male end 1 (as shown in Figure 4, there is also a safety notch in the upper position of the member 30, where the tongue 37 overcomes tooth 8). The member 30 finally incorporates a visual locking indicator 38 which is visible on the male end 1 in the unlocked position of Figures 3 and 4 and invisible on this endpiece 1 in the locking position of Figures 5 to 7, and consists of an axial pin 38 formed in one piece with the member 30 radially inside the tongue 37 and movable in axial translation with the member 30 inside a through housing 4a of the 1 this tip advantageously has a color contrasting with that of the tip 1 to facilitate viewing by the operator of the unlocked position where it is flush with the bearing surface. the locking position which is obtained by pressing down on the member 30, the pin 38 is pressed relative to this surface 4 due to the clipping of the tongue 37 under the tooth 9, thus being invisible to the operator. As illustrated in FIGS. 4 to 6, the procedure is as follows to make, lock and then unlock the connection of the tabs 21 in the groove 13 of the socket 10: a) the member 30 is positioned around the endpiece 1 so that the tabs 21 are preferably above the ramps 7 10 (see Figure 3), b) the tip 1 is pushed to the bottom of the socket 10 to connect it abutting in such a way that the lugs 21 come immediately above the groove 13 (see FIG. 4) being centered precisely on the female endpiece 10 thanks to the ribs 8 of the endpiece 1, 15 c) a thrust is exerted towards the bottom on the member 30 via a clipping of the tongue 37 under the tooth 9 (resulting in a disappearance in view of the pin 38) to bring the tabs 21 in the locked locking position in the groove 13 (see Figure 6) , by their radial flexion in contact with the ramps 7 having guided and then blocked, and 20 d) for unlocking the device, it pulls upward on the member 30 while maintaining the male end 1 against the bottom of the female end 10. Note that the reduced diameter of the tabs 21 minimizes the effort required to obtain the locking position in step 25 c), it being specified that it was not during the establishment of the connection cumulative respective efforts related to the tabs 21 and the seal 16. Finally and as illustrated in FIGS. 7 and 8, the device according to the invention has the advantage of being self-locking in operation, under the effect of the pressure of the fluid circulating in the male end 1 (see arrow 30 A of FIG. FIG. 7 for this circulation of the fluid), thanks to the ramps 7 then further forcing the lugs 21 radially against the groove 13 and resulting in a very high tearing force required to unlock the device.

Claims (15)

CLAIMS1) Connecting device for a fluid transfer line, in particular at low pressure, comprising: - connection means intended to be mounted around a male tubular end piece (1) while being connected to a female tubular end piece (10) by a radially inner face (11) of the latter, the connecting means comprising an axially inner end (20) which can be received in a connection groove (13) of this inner face, and locking means (30) of said connecting means which is adapted to be mounted around the spigot end for reversibly bringing said connecting end into a locking position in said groove, characterized in that the connecting means is formed of in one piece with the locking member of which it forms an axially inner end, this connecting means comprising a bearing zone (36) radially internal intended to be mounted e against the male end and terminating in said connecting end, which comprises at least two tabs (21) elastically deformable in the radial direction and extending the support zone radially outwards, the radially outer faces (24a 24c) and internal (23) of each tab being adapted to be locked in the locking position, by bending each tab respectively against said groove and against a corresponding ramp (7) for guiding and assisting locking that presents the male end. 2) Connecting device according to claim 1, characterized in that each connecting lug (21) has its inner face (23) which has an oblique or slightly concave surface intended to be mounted in contact with a ridge (7a) said corresponding ramp (7) in the locking position, and its outer face (24a to 24c) which has a convex surface whose radius of curvature is adapted to substantially match the profile of said groove (13) in this position. 3) Connection device according to claim 2, characterized in that the outer face (24a to 24c) of each lug (21) comprises two oblique sections axially outer (24a) and inner (24b) and a third intermediate section (24c) which are intended respectively to marry two flared edges (13a and 13b) and a flat bottom (13c) of said groove (13). 4) Connection device according to one of the preceding claims, characterized in that said connecting tabs (21) are each arcuate and interconnected by as many notches (22) designed to make these tabs sufficiently deformable in radial bending . 5) Connection device according to one of the preceding claims, characterized in that the locking member (30) has essentially: - a radially inner annular portion (35) which is intended to be mounted in contact with the male end (1 ) and which has an internal diameter greater than that of said bearing zone (36) that this portion overcomes, and - gripping means (31 and 32) forming an axially outer end of the locking member, preferably at the number of two and diametrically opposed, these means each having a radial thrust surface (31a, 32a) which is intended to receive a manual thrust of an operator towards the female end (10) and which is supported and connected to this portion annular (35) by a connecting portion (33, 34) extending axially and radially inwardly. 6) Connection device according to claim 5, characterized in that at least one means for securing the connection (37) of the connection means to said groove (13) is formed on the locking member (30) in the immediate vicinity said gripping means (31 and 32), and is adapted to be wedged directly under at least one radial projection (9) of the male end (1) in the locking position so as to oppose the exit of said connecting end (20) out of the groove (13) by a rise of the locking member relative to the male end. 7) Connecting device according to claim 6, characterized in that said or each radial projection (9) is formed of a retaining tooth which extends radially outwardly a central bearing surface (4) of the endpiece male (1) and in which is adapted to come jamming by clipping at least one tongue (37), which forms the (s) said means (s) securing the connection and extends radially inwardly one of said gripping means (31). 8) Connection device according to one of the preceding claims, characterized in that the locking member (30) further incorporates a visual locking indicator (38) which is respectively visible and invisible on the male end (1) in the unlocked and locked positions and which preferably comprises at least one axial pin (38) which is formed integrally with the locking member at its axially outer end being movable in translation within a housing (4a) opening on a bearing surface (4) of the male end. 9) Connecting device according to claim 2 and one of claims 3 to 8, further incorporating the male end (1) on which is mounted the locking member (30), characterized in that this male end has said ramps (7) radially projecting, spaced apart on its circumference and at the same axial height, each ramp having: - an upper oblique portion (7b) extending radially outwards and axially inwards according to a acute angle to said ridge (7a), and - an axial portion (7c) extending axially inwardly from said ridge, each of said tabs (21) overlapping in the locking position these two oblique portions upper and axial on either side of this edge, so that these ramps alone block in operation the corresponding tabs in said groove (13) by deforming radially outwardly. 10 10) Connection device according to claim 9, characterized in that said ramps (7) each terminate in a lower oblique portion (7d) and are preferably two in number being diametrically opposed on the male end (1) like said tabs (21) intended to come into contact with them in the locking position. 11) Connecting device according to claim 9 or 10, characterized in that the male end (1) further comprises, between said ramps (7), centering means (8) which are adapted to guide this male end 20 in translation in the socket (10) to facilitate the angular centering of said connecting tabs (21) at the inlet of said groove (13), and which preferably comprise axial ribs (8). 12) Connecting device according to one of claims 9 to 11, characterized in that it further comprises at least one sealing ring (16) preferably toric, which is mounted or overmolded in a sealing groove (6). ) of the male end (1) adjacent to an axially inner end of this male end and which is intended to be applied against the female end (10). 30 13) Fuel injector return circuit comprising a male tubular nozzle (1) connected to a female tubular nozzle (10) by a connection device, characterized in that the device is as defined in one of the preceding claims. 14) A method of mounting / disassembling in the locking position of a connecting device according to one of claims 1 to 12 around a male tubular end piece (1) and in a female tubular end piece (10) to be connected to this male end piece, characterized in that it comprises the following successive steps for mounting the device: a) positioning the locking member (30) around the spigot, preferably such that said connecting lugs (21) are located above said ramps (7), b) pushing the male end to the bottom of the socket to connect to the latter, so that these tabs are located immediately above said throat connection (13), c) an axially inward thrust is exerted on the locking member to bring these tabs into the locking position, by their radial deformation in flexion in contact with said ramps, then d) for unlocking the disp ositive, it pulls axially outwardly on the locking member while maintaining the male end against the bottom of the socket. 15) A method of assembly / disassembly according to claim 14, the connecting device being according to claim 6 or 7, characterized in that to implement step c), it brings the (s) said (s) means (s) securing the connection (37) that has the locking member (30) under said radial projection (s) (s) (9) of the male end (1), preferably by clipping of at least one tongue (37) forming this means under a corresponding retaining tooth (9) forming the or each protrusion.